Key holder



FIG. 1 is an upper left front perspective view of a key holder showing my new design;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a left side elevation view thereof;

FIG. 4 is a right side elevation view thereof;

FIG. 5 is a top plan view thereof; and,

FIG. 6 is a bottom plan view thereof, the key as shown in dashed lines in FIG. 1 form no part of my invention. 

The ornamental design for a key holder, as shown and described. 